2.0Hdi 'misfire'?

[milleplod]

My 70k-miles '09 2.0HDi auto runs very nicely indeed, I'm very pleased with it. However, I've noticed that if I close the throttle sharply....ie lift my foot off the accelerator suddenly....the engine seems to stutter slightly as the revs come off and approach tickover, almost like a misfire. If I lift my foot off more gently, it doesn't seem to do it. Low speed running is fine, acceleration is fine, and if its done the stutter and I then re-apply the accelerator, its fine. Setting off from our drive, engine hot or cold, there's a fairly steep downhill bit - my foot's usually off the accelerator as I roll down the road....gently pressing the accelerator brings on the stuttering feeling every time. I'd say its definitely more obvious on the over-run.

 

Its more of a minor niggle than anything else, my wife hasn't even noticed it....but minor niggles are....well....niggling!

Any ideas anyone?

 

Pete

Edited November 18, 2016 by milleplod

[paul.h]

Maybe there is some wear in the accelerator pedal electrics.

[milleplod]

Thanks for the reply.

 

Would that throw up a fault code do you know?

 

Pete

[paul.h]

I would not expect it to. I replaced the pedal on our previous C3 since that could not gradually increase the revs up to about 2000 rpm and was making it difficult to set off and it did not give any fault codes since it was probably not something that could affect the exhaust emissions. Maybe you could check your car by very gradually increasing the revs with the car stationary and see if the revs go up smoothly.

[milleplod]

At a standstill, engine revs rise smoothly with the lightest of touches on the accelerator. The stutter is definitely most obvious (a) - during an over-run scenario, if the accelerator is lightly pressed. A heavier foot gives no stuttering. And (b) in normal driving, at lower speeds, if the accelerator pedal is 'shut' sharply, as the revs drop to tickover. Odd indeed.

 

Pete